Minecart Sounds 1.4.4 - Sounds like rapid fire

After 1.4.4 was released, I hopped onto a minecart, and instead of hearing the regular rail sound, I heard what sounds similar to a rapid fire gun from other games.

Steps to Reproduce:
1. Hop on a rail
2. Listen
3. Usually occurs on up/down rail slopes, but also has been heard on straight runs.
4. Sound not always present.